Samuel Salman El Reda, a Colombian of Lebanese descent who formerly lived in Buenos Aires, was the top local connection in the attack, Prosecutor Alberto Nisman told a press conference.
The July 18, 1994 bombing of the Argentine Jewish Mutual Association, a Buenos Aires headquarters of Jewish charity groups, has gone unsolved for a decade and a half.
A 1992 bombing of the Israeli Embassy in Buenos Aires that killed 22 and wounded 200 also remains unsolved.
Argentina has South America's largest Jewish community.
El Reda has been married to an Argentine national, Silvina Sain, since 1989 "and was part of the most radicalized sector of the local Muslim community," Nisman said.
El Reda has relatives in Lebanon, where he had recently been living with his wife, Nisam said.
Argentine Judge Rodolfo Canicoba Corral, in charge of the case, earlier called for the arrest of several former Iranian officials in connection with the bombing, including ex-president Ali Akbar Rafsanjani, former security minister Ali Fallahijan, ex-foreign minister Ali Velayati, former Revolutionary Guard chief Moshen Rezai, and Mohsen Rabbani, who worked at Iran's embassy in Buenos Aires.
"It has been proven that El Reda was one of the people Rabbani trusted the most," said Nisman, adding that the Colombian suspect ran two safe houses in Buenos Aires.
Officials in Tehran have rejected all charges linked to the case, and has refused to collaborate with Argentine investigators.
Nisman also said that El Reda placed calls to the Shiite group Hezbollah in Beirut, as well as to a mobile phone located in the "tri-border" area, a zone between Argentina, Paraguay and Brazil suspected of being a haven for radical Islamic groups.
El Reda's trail went cold two hours before the blast, and 40 minutes before the departure of the only flight of the day to Puerto Iguazu, on the Argentine part of the "tri-border,"Nisman said.
